Merge pull request #70 from outcoldman/cluster_select

When node is getting filtered because of the latency - the count of nodes should be decremented

Author: chergert

src/mongoc/mongoc-cluster.c

@@ -770,6 +770,7 @@ _mongoc_cluster_select (mongoc_cluster_t             *cluster,
          if (nodes[i]) {
 			 if (nodes[i]->ping_avg_msec >(int32_t)watermark) {
                nodes[i] = NULL;
+               count--;
             }
          }
       }